Cable cutter



March 30, 1965 CABLE CUTTER Filed Oct. 11, 1962 FIG.4

Fl 6 3 INVENTORS.

MEREDITH W.WILTERDINK BY THOMAS F. HUSEN AT RNEY United States Patent 3,175,289 CABLE CUTTER Meredith W. Wilterdinlr, Easton, Conn, and Thomas F. Hursen, Monroeville, Pan, assignors to The Ballard Company, Bridgeport, Conn, a corporation of l Connecticut Filed Oct. 11, 1962, Ser. No. 229,924

3 Claims. (Cl. 30-180) The present invention relates to cable cutters and particularly to a new and improved explosively operated" cable cutter capable of use above or under water. It is understood that cable cutting is intended to embrace the cutting of rods, pipe and other similar articles, as well as the punching of holes and driving of studs or projectiles.

The principal object of the invention is to provide an explosively operated cable cutter of minimum size and weight.

Another object of the invention is to provide such a cable cutter that is capable of use under water with no appreciable noise or any evidence of flash or gas bubbles.

Still another object of the invention is to provide such a cable cutter in which one size of charge is capable of cutting all sizes of cables within the capacity of the device.

A still further object of the invention is to provide another version of a cable cutter in which the cutting blade has some free travel before it strikes the cable to utilize the kinetic energy built up during this free travel and thereby reduce the explosive charge required.

In one aspect of the invention, a cable cutter may comprise a C-shaped member in which an anvil is provided within one end portion thereof and a bored cylinder is formed in the other end in aligned relation with the anvil. A piston having one end in blade form may be mounted within the cylinder, and a gas seal or the like may be provided between the cylinder bore and piston.

In another aspect of the invention, the piston may be bored and counterbored in its end opposite the blade end, and a compression spring may be located between a safety disk at the bottom of the counterbore and an end closure of the cylinder. The bore within the piston forms an escape chamber ahead of the safety disk, and it may include a port leading to atmosphere.

In still another aspect of the invention, the cylinder closure may support a cartridge and a spring operated firing pin that normally is held in cocked position away from the cartridge primer by a latch which is capable of cocking and releasing the firing pin by a lanyard ring connected to it.

In still another aspect of the invention, the piston blade may be held in retracted position, with the compression spring between it and the closure compressed, by a withdrawable pin, so that it is only necessary to hook the anvil portion of the C-shaped housing onto a cable and to withdraw the blade pin. This will cause the compression spring to expand, forcing the piston blade against the cable, thus securing the device to the cable.

In still another aspect of the invention, the compression spring between the piston blade and cylinder closure may be eliminated, permitting a reduction in the overall size of the device, and the piston blade may be held in retracted position by a frangible pin. In such case, a separate spring clip may be provided for holding the device onto a cable to be cut.

The above, other objects and novel features of the invention will become apparent from the following specification and accompanying drawing which is merely exemplary.

In the drawing:

FIG. 1 is a view of a cable cutter to which the principles of the invention have been applied;

FIG. 2 is a sectional View taken substantially along line 2-2 of FIG. 1, but with certain parts in positions different from those of FIG. 1;

FIG. 3 is a sectional View of a modified form of cutter to which the principles of the invention have been applied; and

FIG. 4 is an end view of the cutter shown in FIG. 3.

Referring to the drawings, and particularly to FIGS. 1 and 2, the principles of the invention are shown as applied to an explosively operated cable cutter including a housing it which may include a hook-like end portion 11 having an anvil surface 12 provided therein. The member 10 may have its opposite end bored to form a cylinder 13 within which may be mounted a piston 14-. An O-ring seal 15 or the like may be provided between the piston 14 and cylinder 13 for excluding water from the interior of cylinder 13 when the device is used under water, and a brass or other soft metal washer 1o may be fixed to the end of piston 14 within the cylinder 13. The washer l6 acts as a high-pressure seal to prevent the escape of gases upon detonating the explosive charge and to preclude the rise of bubbles through the water when the device is discharged.

The piston 14 extends out from cylinder 13, and its end opposite that containing the washer 16 may be tapered to form a blade 17. The end of piston 14 containing the washer 16 may be bored to form a chamber 13 and counterbored to form a pocket 19. A safety blow-out disk 20 may be located between pocket 19 and chamber 18, and a port 21 may lead from chamber 18 to atmosphere.

A compression spring 22 may have one end seated on the blow-out disk 20 and its opposite end abutting a closure 23 for the end of cylinder 13 opposite that through which blade 17 extends. The closure 23 may be threaded into the end of cylinder 13, and a seal 24 such as an D-ring may be provided for preventing leakage past the threads. The closure 23 may be provided with a bore 25, a counterbore 26 and a second counterbore 27. A blank cartridge 28 is adapted to be mounted within the counterbore 2-7 with its and containing the primer cap abutting a disk 29 that rests on the shoulder formed between counterbores 26 and 2-7. The cartridge 28 is retained within counterbore 27 by a snap ring 3a).

A firing pin 31 may be mounted within counterbore 26. It may include a head or piston portion 32 having axially extending peripheral grooves 33 thereon for a purpose to be explained later. It may be fixed to a rod 34 that extends axially through counterbore 26 and through bore 25 to the exterior of the device. A spring 35 may be located within counterbore 26 between the piston 32 and a shoulder between bore 25 and counterbore 26. The forward end of piston 32 may include a sharp end 36 that is aligned with, and adapted to pass through, a hole 37 in disk 29.

The rearward end of rod 34 may be provided with a cam surface 38 that mates with a cam surface 39 on a head 40. The construction is such that with the cam surfaces 38 and 39 in mating relation, they form a latch that slidingly fits within bore 25, and head ill abuts the outer end of closure 23, holding pin 36 retracted from the primer cap of the cartridge 28.

An O-ring seal 41 may be provided between the rod 34 and bore 25 to the right of the cam surfaces 38, 39 for a purpose to be described later. A lanyard ring 42 may be connected to the head 40.

Normally, the device is loaded and the blade 17 is held in a rearward position by a pin 42 (FIG. 2) having a withdrawing ring 43 connected to it. This provides an open- 3 ing 44 leading to the anvil 12 so that the device can be hooked onto a cable 45 or the like, after which pin 42 is withdrawn, causing spring 22 to force the blade 17 into contact with the cable 45. Pulling the lanyard ring 42 leftwardly causes the firing pin 31 to move leftwardly against the action of spring 35 until cam surfaces 3 3, 39 are outside of bore whereupon they separate. The spring accordingly forces firing pin 31 rightwardly, and its pin 36 detonates the primer cap of the cartridge 28, causing the expanding gases therefrom to force piston 14 and its blade 17 rightwardly, severing the cable 45.

The O-ring '15 prevents the admission of water into cylinder 13 when the device is used under water, and the high-pressure brass seal 16 traps the high-pressure gases within cylinder 13 after the cartridge has been fired to prevent the rising of bubbles Within the surrounding water.

Should any of the expanding gases move rearwardlly, they are permitted to pass through the rooves 33 on piston 32 to prevent piston 32 from being forced rearwardly against spring 35 with sufficient force to damage said spring. The O-ring seal 41 is intended to prevent any such backward moving gases from escaping into the surrounding water.

Referring to FIGS. 3 and 4, the principles of the invention are shown as applied to a cutter including a housing 46 containing a hook-like end portion 47 having an anvil 48. The end of housing 46 opposite that including anvil 48 may be bored and counterbored at 4'9 and 50. A piston 51 having a blade 52 may be mounted in bore or cylinder 49, and it may be provided with a bore 53 and a counterbore 54.

The embodiment of FIG. 3 omits the spring 22 of FIG. 1, and the piston 51 is normally maintained retracted by a frangible pin 55 mounted in the housing 46 against which the blade 52 of piston 51 abuts. A cup-shaped element 56 may be mounted within counterbore 54 and it may have a safety blow-out end 57 that functions similarly to the disk 26 of FIG. 1, and when ruptured, permits the expanding gases to vent to atmosphere. Normally, however, the safety blow-out elements 56, 57 are strong enough to cause proper functioning of the piston 51 to effect severance of the cable 45.

The element 56 extends slightly beyond the end of piston 51 and supports a brass or other metallic Washer seal 58 for preventing the escape of gases from the cylinder 4-9 when the device is operated. The piston 51 and washer 58 are held in abutting relation with the forward end of a closure 59 that is threaded into counterbore 5b. The closure 59 in the embodiment of FIG. 3 contains a cup-shaped element 60 but in reverse relation to cupshaped element 56. The element 60 may include an aperture 61 for the reception of the pointed end of firing pin 62 which latter functions simlarly to firing pin 31 of FIG. 1. A cartridge 62" may be located within the chamber formed by the cup-shaped elements 56 and 65.

From the foregoing it is evident that the embodiment of FIG. 3 is much smaller in size than that of the embodiment of FIG. 1; however, the piston 51 of FIG. 3 cannot be employed to hold the cutter onto the cable 45. Accordingly, a spring arrangement is provided for this purpose. Referring to FIGS. 3 and 4, a pin 63 may extend transversely through and beyond the housing 46, and coils 64 and 65 of a spring may be mounted on said pin 63 on opposite sides of the housing 46. One end of coils 64, 65 are joined by a looper portion 66 that may be used to support the device on a hook when not in use. The opposite ends of coils 64, 65 may be connected to separate legs 66, 67 that extend beyond the end of hook portion 47 and which legs can be easily forced in a clockwise direction (PIG. 3) when cable 45 is inserted in hook portion 47 on anvil 48. The legs 66, 67 are placed under A1 a torsional stress by the coils 64, 65 and retain the device on cable 45 with piston 51 in its retracted position.

Although the various features of the explosively operated cable cutter have been shown and described in detail to fully disclose two embodiments of the invention, it will be evident that changes may be made in such details and certain features may be used without others without departing from the principles of the invention.

What is claimed is: a

1. In a cable cutter, a hook-shaped member having a anvil formed at its one end; a cylinder within said member aligned with said anvil; a piston within said cylinder having a blade end extending outwardly toward said anvil from one end of said cylinder, said piston being provided with a safety expansion chamber ported to atmosphere; safety blow-out disk means separating said safety chamber from said cylinder; a closure for the other end of said cylinder; means within said closure for supporting a cartridge therein; a firing pin in said closure aligned with said cartridge-supporting means; means at the end of said piston opposite said blade for preventing water from entering said cylinder; and deformable, soft metal means mounted on the end of said piston opposite said blade end for preventing the escape of gases from said cylinder upon detonating said cartridge.

2. In a cable cutter, a hook-shaped member having an anvil formed at its one end; a cylinder within said member aligned with said anvil; a piston within said cylinder having a blade end extending outwardly toward said anvil from one end of said cylinder, said piston being provided with a safety expansion chamber ported to atmosphere; safety blow-out disk means separating said safety chamber from said cylinder; a closure for the other end of said cylinder; means Within said closure for supporting a cartridge therein; a spring between said closure and said blow-out disk means; a firing pin in said closure aligned with said cartridge-supporting means; means at the end of said piston opposite said blade for preventing water from entering said cylinder; and means mounted on the end of said piston opposite said blade end for preventing the escape of gases from said cylinder upon detonating said cartridge.

3. In a cable cutter, a hook-shaped member having an anvil formed at its one end; a cylinder within said member aligned with said anvil; a piston within said cylinder having a blade end extending outwardly toward said anvil from one end of said cylinder, said piston being provided with a safety expansion chamber ported to atmosphere; a closure for the other end of said cylinder; oppositely facing cup-shaped means within said piston and closure, forming a cartridge-supporting chamber, one of said cupshaped members providing a safety blow-out means; a firing pin in said closure aligned with said cartridge-supporting means; means at the end of said piston opposite said blade for preventing water from entering said cylinder; and deformable, soft metal means mounted on the end of said piston opposite said blade end for preventing the escape of gases from said cylinder upon detonating said cartridge.

References Cited by the Examiner UNITED STATES PATENTS 39,112 7/63 Berney 144.5 X 2,140,338 12/38 Temple 144.5 X 2,455,825 12/48 Temple 1--44.5 2,755,550 7/56 Benjamin 30180 2,897,799 8/59 Stupian 30-180 X 3,003,235 10/61 Temple et al. 30-480 3,036,307 5/62 Voelz et al. 1-44.5 3,036,798 5/62 Martin 30l80' WILLIAM FELDMAN, Primary Examiner. 

1. IN A CABLE CUTTER, A HOOK-SHAPED MEMBER HAVING AN ANVIL FORMED AT ITS ONE END; A CYLINDER WITHIN SAID MEMBER ALIGNED WITH SAID ANVIL; A PISTON WITHIN SAID CYLINDER HAVING A BLADE END EXTENDING OUTWARDLY TOWARD SAID ANVIL FROM ONE END OF SAID CYLINDER, SAID PISTON BEING PROVIDED WITH A SAFETY EXPANSION CHAMBER PORTED TO ATMOSPHERE; SAFETY BLOW-OUT DISK MEANS SEPARATING SAID SAFETY CHAMBER FROM SAID CYLINDER; A CLOSURE FOR THE OTHER END OF SAID CYLINDER; MEANS WITHIN SAID CLOSURE FOR SUPPORTING A CARTRIDGE THEREIN; A FIRING PIN IN SAID CLOSURE ALIGNED WITH SAID CARTRIDGE-SUPPORTING MEANS; MEANS AT THE END OF SAID PISTON OPPOSITE SAID BLADE FOR PREVENTING WATER FROM ENTERING SAID CYLINDER; AND DEFORMABLE, SOFT METAL MEANS MOUNTED ON THE END OF SAID PISTON OPPOSITE SAID BLADE END FOR PREVENTING THE ESCAPE OF GASES FROM SAID CYLINDER UPON DETONATING SAID CARTRIDGE. 